The 2005 or later Chrysler 300, Dodge Charger or Magnum vehicles using the NAG1 transmission might develop an array of nagging transmission related diagnostic codes. These codes could be immediate hard codes or they might pop up intermittently. A more fitting name for this transmission under the circumstances could be NAGMANY instead of NAG1 with the variety of codes it could set.
This transmission has been on the road for many years now originating in Mercedes vehicles and is referred to as 722.6. This transmission is known for having issues with the conductor plate mounted on top of the valve body and for transmission fluid wicking up the wiring harness loading the TCM. These two commonly known problems cause similar nagging code problems that Chrysler and Dodge vehicles experience.
You can suspect the same issues with Chrysler and Dodge vehicles, but you also can add another possibility to the list that does not apply to Mercedes vehicles. It has to do with the way the wiring harness for the TCM is routed. The TCM has two connectors plugging into it called the C1 and C2 connector. The C1 connector typically contains a data line along with TCM power and ground wires. The C2 contains all the solenoids, Fluid Temp, CAN High and Low and N2/N3 input rpm sensor wires.
The placement of the TCM wiring harness has been the cause to this concern. The C1 or C2 harness has been routed over the parking brake bracket, and in time becomes compromised by rubbing through on the support bracket. Depending on the severity of the wear and the harness affected, there will be different types of intermittent or consistent codes set. A simple re-routing and repair of the harness is all that’s needed to resolve the NAG1 nagging issue.
